898 PLANT COMMUNITIES AXD FLORAS. 



scanty knowledge of the plant-communities of Central and Noi-them Europe, and in 

 many extensive tracts as good as nothing is known concerning the most important 

 of all the data required for a demarcation of floral areas. There is nothing for it, 

 therefore, for the present but to grope along with the help of the little that has been 

 ascertained, and in the case of many districts to retain the demarcations laid down 

 by earlier investigators, notwitlistanding the fact that they are based upon altogether 

 different foundations. 



According to this system, the various Floras maj- be roughly distinguished as 

 follows : — 



1. Arctic Flora. The northern parts of Europe, Asia, and North America, extending south- 



wards about as far as to the Arctic Circle. 



2. Baltic Flora. Scaudiuavia, Great Britain, North-German Lowlands, Western Bussia encroach- 



ing to the south on the Floras of the Mediterranean and Black Sea. 



3. Flora of the Blacl< Sea. South-eastern Europe, Asia Minor with the exception of its soutbem 



and western shores, the Caucasus, Kurdestan, Persia : environs of the Caspian Sea. 



4. Mediterranean Flora. Shores of the Mediterranean: Southern Europe, the western and 



southern shores of Asia Minor. Coasts of SjTia, Egypt, Tunis, and Algiers. 



5. Atlantic Flora. Azores, Canary Islands, western shores of the Spanish Peninsula, Morocco. 



6. Siberian Flora. The plain extending from the river Obi and its sources to the Stanovoi 



Mountains. 



7. Kamschatkan Flora. North-east Asia as far south as the region of the Amur Eiver. 



8. Amur Flora. Amur district, Manchuria. 



9. Chinese Flora. China, Japan, extending nearly as far south as the Tropic of Cancer. 



10. Flora of Central Asia. Mongolia, Thibet, bounded to the west by the Steppe-region of the 



Sea of Aral, and to the south by the Hindu Kush and the Himalaya. 



11. Flora of South Arabia and Mesopotamia. Northern shores of Somali, South Aaabia, 



Mesopotamia ; shores of the Persian Gulf. 



12. Sahara Flora. The Sahara to about 15° N. Lat., Northern Arabia. 



13. Soudanese Flora. Bounded on the north by the Sahara, on the south by 10° N. Lat., to the 



east by the mountainous region of Abyssinia, 



14. Flora of Guinea. From 10° N. Lat to 10° S. Lat., eastwards to 35° E. Long. 



15. Zambesi Flora. From 10° S. Lat. to the Orange Eiver on the south, and bounded to the 



ea.st by the Drakenberg Mountains and Lake Nyassa. 



16. Abyssinian Flora. Abyssinia and the mountains adjoining it on the south. 



17. East African Flora. From the shores of the Indian Ocean to the East African Mountains, 



northwards as far as 8° N. Lat. 



18. The Cape Flora. The south-western part of the Cape, bounded to the north by the Great 



Karroo Desert. 



19. Madagascan Flora. Madagascar. 



20. Indian Flora. Bounded to the west by the Indus, to the north by the Himalaya and the 



Yunnan mountains, and extending eastward as far as the Straits of Lomboc and Macassar. 



21. Pacific Flora. Pacific Islands from the Moluccas to the Marquesas Islands on the one hand, 



and from the Sandwich Islands to New Zealand on the other. 



22. Tasmanian Flora. Victoria, Tasmania, New South Wales, and adjoining regiona 



23. Australian Flora. Interior and Western Australia. 



24. Canadian Flora. Bounded to the north by the Arctic Flora, and reaching westward as far 



as the Rocky Mountains, and southward as far as the North American Lakes. 



25. Columbian Flora. Bounded on the north by the Arctic Flora, on the east by the Eocky 



Mountains, on the south by 50° N. Lat 

 2(5. Mississippi Flora. Extending northward to the Lake region, southward to Florida, exclusive 

 of the southern third of that Peninsula, and bounded to the west by 95° W. Long. 



